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Risks of Cannabis on Fertility, Pregnancy, Breastfeeding and Parenting

I Introduction
II Cannabis and Parenting
III Key Messages
IV Conclusion
V Resources

By Marie Brisson, Best Start Resource Centre


I Introduction

Cannabis use is increasing in Canada and it is presently the most commonly used illicit substance. This trend is concerning as most people lack awareness about its health risks. Use of cannabis is already played down and the upcoming legislation may further trivialize its use.

Consumption of dried cannabis for medical purposes has been permitted in Canada since 2001. The Access to Cannabis for Medical Purposes Regulations (ACMPR) has been in effect since August 2016.

Legalization of cannabis is expected to take place July 2018. Its legalization doesn’t necessarily make it safe. Some provinces are asking to delay legislation of cannabis. There are numerous regulatory concerns when considering the impact of legalization from a public health and safety perspective in Canada -- for example, decisions about the precise course of action regarding legislation and distribution, recommended age of use, risk reduction strategies, medicinal use guidelines, awareness of the effects of cannabis use, key public messages, measuring cannabis impairment for drivers, marketing cannabis products, etc. With these upcoming legislative changes, research and best practices guide us in formulating key messages about the risks of cannabis.

This article will touch briefly about the use of cannabis pre and post pregnancy and when parenting. Using cannabis can have effects on health, learning, relationships, fertility, pregnancy and children.

In March 2017, the Best Start Resource Centre released the booklet Risks of Cannabis on Fertility, Pregnancy, Breastfeeding and Parenting. This resource summarizes the current knowledge about the effects of cannabis. It is available in print and PDF and is also available in French.

Key experts within Ontario and Canada provided input during the development of this resource. The booklet was focus tested with English- and French-speaking parents.


II Cannabis and Parenting

Parents’ knowledge gap is worrisome, for example thinking that they drive or parent better while high.

The booklet Risks of Cannabis on Fertility, Pregnancy, Breastfeeding and Parenting presents the following facts based on research and best practices:

  • Cannabis use may affect the ability to become pregnant.
  • Tetrahydrocannabinol (THC) crosses the placenta from the pregnant person to the fetus.
  • For heavy cannabis users and for those who also use tobacco, cannabis may increase the risk of preterm birth.
  • Effects on the fetus are lower birth weight, lower alertness, and slower growth of the new baby. The effects on the baby’s developing brain may be lasting as the baby grows to adulthood.
  • THC passes into breast milk and is taken into a baby’s fat cells and brain. It can be stored for weeks.
  • As a result of exposure to cannabis during pregnancy, a child may have difficulties with learning, behaviour, and mental health in later life. The effects of cannabis use during pregnancy are more common among children of heavier users.
  • If a child eats cannabis it can make them very sick.
  • There are risks in edible cannabis products because when growing and processing cannabis it can be exposed to molds, bacteria, heavy metals and pesticides.
  • Being high while parenting can affect how you interact with your child. It can also affect your ability to judge, to make good decisions and to protect your child from danger. Feeling more relaxed and mellow can result in a slower reaction time and reduce your ability to attend to your child.
  • Being high while driving slows your reaction time and your decision making skills. Driving at a slower speed does not make it safer for you, for those in the vehicle, or for others on the road. Cannabis use increases the risk of a collision.

There are different types of cannabis. The effects depend on the amount of tetrahydrocannabinol (THC), Cannabidiol (CBD), other chemicals, and their interactions. The concentration of THC in cannabis increased from 1.5% in 1960 to 11% in 2014. Cannabis oils have the highest percentage of THC. The effects of heavy cannabis use (1 or more joints per day) can last for several weeks, and perhaps even for years after stopping use.

There is a possible association between heavy regular cannabis use and the risk of developing or worsening mental health symptoms. As well, for people -- such as those with a personal or family history of mood and anxiety disorders -- who are at high risk for mental health issues, the use of cannabis can make the illness and symptoms worse. In particular, there is a risk of a psychotic episode after cannabis use for those at risk.

There is increasing evidence that cannabis is harmful to brain development, especially if it is used before the age of 25 years.

Are the evidence-based interventions for preventing cannabis use flexible and responsive enough to change trends in cannabis use in those planning a pregnancy, those who are pregnant, and parents? As the potential medical benefits are being hyped by cannabis producers -- for example, claims that it helps morning sickness -- it’s no wonder that youth and adults are confused about the safety of cannabis.


III Key Messages

Key messages from the booklet for parents-to-be and future parents include:

  • There is no known safe amount of cannabis use in pregnancy and when breastfeeding. Abstinence is recommended.
  • If you are unable to stop using cannabis completely, try using less and less often.
  • If a child eats cannabis, get medical help right away.
  • It may be risky to buy and use food products containing cannabis due to lack of regulation and inspection of the cannabis industry.
  • If a parent is high, be sure that there is always someone available who is not high to take care of the child’s needs.
  • Cannabis impairs the ability to operate a motor vehicle safely. Never drive while impaired, with or without a child in the car.
  • Keep learning about the effects of cannabis as new information becomes available. Discuss your ideas and concerns with your health care provider.


IV Conclusion

We can draw useful lessons from the experiences of other jurisdictions have legalized the use of cannabis. However, more research is needed about the impact of cannabis on child development; the long and short term impact of cannabis use during pregnancy, breastfeeding and when parenting; and the connection between cannabis use and mental health.


V Resources


Canada’s Lower-Risk Cannabis Use Guidelines (LRCUG)

Lower-Risk Cannabis Use Guidelines for the public

Lower-Risk Cannabis Use Guidelines (LRCUG) for professionals


Canadian Centre on Substance Use and Addiction

Clearing the Smoke on Cannabis series


Canadian Paediatric Society

Position Statement - Cannabis and Canada’s children and youth


Ontario Public Health Association

The Public Health Implications of the Legalization of Recreational Cannabis - Position Paper


You can view the webinar recording of Perinatal Cannabis Use: Implications for Pregnancy, Lactation and Parenting presented by Dr Alice Ordean.

To stay current and learn about the current status of cannabis laws in Canada and the work being done to legalize and regulate it, refer to the government of Canada site.